MnSO 4 -promoted S-O bond cleavage for synthesizing functionalized sulfonium ylides from activated alkynes and sulfoxides.

A variety of functionalized sulfonium ylides were prepared in good yields through MnSO 4 -promoted S-O bond cleavage from activated alkynes and sulfoxides. Experimental results showed that the MnSO 4 catalyst played important roles in accelerating the reaction and promoting the [1,3]-rearrangement of the S-O bond. Furthermore, the product was easily obtained on a gram scale by simple recrystallization without column chromatography. The obtained product can be converted to new sulfonium ylides and undergo cycloaddition with an alkyne to afford a trisubstituted furan scaffold.